The GMC EGR valve is important to the smooth and efficient operation of your engine, playing a role in two vehicle systems to support its function. In most vehicle models, the GMC EGR valve is mounted to the intake manifold of the engine, operated mechanically with a vacuum connection in older model vehicles, electronic in the late model vehicle. The GMC EGR valve is important to the regulation of exhaust emissions, helping to maintain a level of pollution that is acceptable under the strict vehicle emissions regulations in place today. The GMC EGR valve helps to ensure a clean burn of fuel during engine combustion, keeping the unburned fuel left in the cylinder after combustion to a minimum. This reduces the amount of harmful chemicals produced by the vehicle with the evaporation of excess fuel. The GMC EGR valve also helps to prevent detonation in the engine combustion chambers, which produces a knocking sound in the engine. Engine knock can be very harmful to the engine, causing damage to delicate parts. Detonation, or engine knock, is the explosion of fuel in the cylinder, rather than the clean burn of fuel that provides efficient engine power and performance. The intense heat and pressure that detonation creates can damage the combustion armor in the cylinders, allowing the force of combustion to escape from the cylinders to damage engine seals and components. Our online catalog features a selection of quality GMC EGR valve replacements to keep your engine operating at its best. Our great prices and expert customer service will make ordering your GMC EGR valve easy on both you and your budget, whether you use our secure and efficient site or our convenient toll-free phone line.